检测日本血吸虫感染者血清中特异性IgG4的诊断价值

为评价日本血吸虫感染者血清中特异性IgG4的诊断和疗效价值，本研究以SEA为抗原，胶体金．抗人IgG4单抗结合物为检测标记物，以金标免疫渗滤法（DIGFA）检测急性和慢性血吸虫病患者治疗前后血清中特异性IgG4抗体。结果显示，急性和慢性血吸虫病病人血清中IgG4阳性率分别为90．9％（30／33）和98．0％（98／100）；检测非疫区健康者血清及其他寄生虫（包括肺吸虫、华支睾吸虫、囊虫等）感染者血清共235人份，未有阳性出现（特异性为100％）；检测急性血吸虫病病人治疗后6个月和12个月血清，IgG4抗体的阴转率分别为52．0％（13／25）和87．5％（21／24），均明显高于IgG阴转率；检测血吸虫病病人治后6个月血清，慢性病人与急性病人IgG4抗体阴转率无差异。结果表明DIGFA法检测病人血清特异性IgG4诊断血吸虫病敏感性高，与IgG相比有更高的特异性，具有一定的疗效考核价值。

DIAGNOSTIC VALUE OF RAPID DETECTION OF SPECIFIC IgG4 IN SERA OF PATIENTS WITH SCHISTOSOMIASIS JAPONICA

In order to determine the value of Schistosome-specific IgG4 in diagnosis and evaluation of chemotherapy efficacy of schistosomiasis, a simple field-applicable assay, dot immuno-gold filtration assay (DIGFA), was developed for rapid detection of schistosome-specific IgG4 in the sera of individuals. Soluble egg antigen (SEA) and monoclonal antibody of S. japonica against human IgG4 were used as diagnostic reagents. Total 437 sera from patients with acute or chronic schistosomiasis, other helminthiasis and healthy donors were detected by DIGFA-IgG4. The results showed that the sensitivities for acute and chronic patients were 90.9% (30/33) and 98% (98/100) respectively. All of sera from healthy donors and patients infected with other helminthiasis such as paragonimiasis, clonorchiasis, cysticercosis and intestinal nematode showed negative result. 52.0% (13/25) and 87.5% (21/24) of cases showed SEA-IgG4 negative on 6 months and 12 months post-treatment respectively, and obviously higher than those of SEA-IgG (P<0.05). In conclusion, SEA-IgG4 assay has higher specificity than SEA-IgG assay with similar sensitivity. Moreover, antibody negative conversion rate of SEA-IgG4 is obviously higher than that of SEA-IgG post treatment. These results suggest that rapid detection SEA-IgG4 with DIGFA will have an important role in the diagnosis and evaluation of efficacy of therapy of schistosomiasis japonica.